This invention relates to a liquid fuel vaporizer and burner unit for a room air space heater wherein primary combustion air is mixed and preheated with the vaporized fuel and secondary combustion air is force fed to the ignited mixture.
Liquid fuel burners are known wherein the fuel, such as kerosene, is supplied to a rotary splash or scattering plate and thrown thereby against a heated vaporization surface. Force fed combustion air, supplied by a blower or the like, is mixed with the vaporized fuel and jetted through flame holes in a burner plate into a combustion chamber, where the mixture is ignited.
In such conventional burners, however, the premixing distance for the combustible fuel-air mixture is relatively short, whereby uniform pre-combustion mixing is inhibited and incomplete, and inefficient burning results. To overcome this difficulty it is necessary to specially design the flame holes in the burner plate, which renders them susceptible to carbon clogging and impairs the heating capacity of the device. Furthermore, since the fuel scatterer comprises a rotary plate and the vaporization surface completely surrounds it, the configuration of the conventional device is generally bulky and inconvenient, which imposes a severe limitation on its use and attractiveness in the average room. Examples of such prior art devices are found in U.S. Pat. No. 3,964,859 and U.S. patent application No. 600,378 filed on July 30, 1975 now U.S. Pat. No. 4,045,159.